Question

Task 1. Situational tasks:

A 4-day-old newborn was delivered to the clinic. From the history of the disease it is known: a child from a second pregnancy, full-term, birth weight is 3500g. Pregnancy proceeded normally, childbirth was normal. The child cried immediately. After trying to give the child a drink of sweet water a cough, cyanosis and vomiting appeared. During feeding expressed breast milk from a spoon, vomiting, cyanosis also appeared immediately, and foam flowed through the nose. Vomit is without signs of caseation. On the third day, the doctor suspected a child with a malformation - atresia of the esophagus.

Questions for discussion:

1. What are the mechanisms of this embryopathy?

2. What types of apoptosis and their distinctive features do you know?

3. What type of apoptosis occurs with atresia? Explain.

Answer 1

1. mechanisms of this embryopathy

The fundamental morphogenetic process appears to be a rearrangement of the proximal foregut into separate respiratory (ventral) and gastrointestinal (dorsal) tubes. This process depends on the precise temporal and spatial pattern of expression of a number of foregut patterning genes. Disturbance of this pattern disrupts foregut separation and underlies the development of tracheo-oesophageal malformations.

2.types of apoptosis and their distinctive features 

The two major types of apoptosis pathways are “intrinsic pathways,” where a cell receives a signal to destroy itself from one of its own genes or proteins due to detection of DNA damage;and “extrinsic pathways,” where a cell receives a signal to start apoptosis from other cells in the organism. The extrinsic pathway may be triggered when the organism recognizes that a cell has outlived its usefulness or is no longer a good investment for the organism to support.

3.type of apoptosis that occurs with atresia

Granulosa cell apoptosis is promoted by tumor necrosis factor-alpha (TNFα), though the mechanism of TNFα is unclear.

tumor necrosis factor alpha (TNF alpha) and receptors

  Fas ligand and receptors

  TNF-related apoptosis-inducing ligand (TRAIL; also called APO-2) and receptors

  APO-3 ligand and receptors

  PFG-5 ligand and receptors

TNF-related apoptosis-inducing ligand TRAIL activates Caspase 3 (CASP3), which in turn interacts with caspases 6, 7, 8, 9, and 10 to induce apoptosis in granulosa cells.